Grate



Aug. 16, 1927.

s.v s. s. Y KENNEDY GRATE Sheets-Sheet l Filed Juiy 8, 1925y w I 1,639,343 Aug. 16 1927 s. s s. K ENNEDY A GRATE Fil'ed July 8, 1925 2 Sheets-Sheet 2 I V31a/mundo@ Patented Aug. 16, 1927.

. UNITED .STATES sTErHnN sQs. KENNEDY, or PONTIAC, MICHIGAN;

GnA'rn.

Application led July 8, 1925. Serial No. 42,225.

The present invention relates to grates and aims to providea novel and improved device of this Acharacter which is more `especially'adapted for use in burning bitumi nous or soft coal,said grate being so constructed that coal burned thereon will give` off' an intense heat and practically all combustible particles of the coal will be ignited, whereby the utilization of coal is minimized to ka great extent.`

Another object of the invention is vvto provide a grate having a series of air charnbers arranged to extend upwardly ina fire box for receiving air therein under pressure, said chambers having communication to the fire box through openings at the sides of: the chambers, whereby the air underpressure from the various chambers will be directed in the fire boX more in horizontal direction than a vertical direction, thus eliminating to a great extent combustible particles of coal being blasted to and pass the boiler before being properly ignited, which would reduce the efficiency of the coal consumed.

A further object of the invention is the provision of a grate constructed of a series of units, each consisting of a raised portion which is reinforced at a certain point for preventing sagging when the units are subjected to a high temperature, and a flange at the base of the raised portion upon which are placed fire bricks for retaining the units in place.

lt is also an object of the invention to provide a grate of the kind indicated, which is simple and substantial which can be manufactured economically, and which will be thoroughly efficient and practical in use,

vW'ith the foregoing and other objects in view, which will be apparent as the description proceeds, the invention resides in the construction and arrangement of parts, as hereinafter described and claimed, it being understood that changes can be made within the scope of what. is claimed, without departing from the spirit of the invention.

The invention is illustrated in the accompanying drawings, wherein: Y

Figure 1 is a Vertical cross section of a furnace showing my improved grate applied thereto,

Figure 2 is a horizontal section taken on line 2 2 of Figure 1,

Figure 3 is a top plan of one units,

f the grate in construction,-

Figure 4 is aV fragmentary side elevation of the same, showing a portion thereof in section, f

Figure 5 is an end elevation of a Section, and.

Fig-ure .-6 is a cross section of a grate section taken lon line 6 6 of Figure 4,

vReferring to the drawings by numerals, 10 designa-tes a furnace having side walls l1 whiehsupport a boiler 12. Arranged at the front of the furnace is a pair of doors 13 for permitting access to there box le. In carrying out my invention, the numeral 15 indicates a floor for the furnace'which is constructed of fire bricks and fire clay. Supported ont-he oor 15 is a series of metallie grate members 16, which are semi-cylindrioalk so as' to provide raisedy portions 17. At the lower edges of the semi-cylindrical Sectiousare provided. c0nt'11uOus`flangeS 1S which ret upon the Hoor 15, said flanges having placed thereon re bricks 19 which are held in place by fire clay for retaining said semi-cylindrical sections in their proper positions.

The semi-cylindrical sect-ions 17 have their opposite ends closed, as at 20, so as to form an air chamber in each section, the floor 15 serving as a means for closing the bottom of said section. The semi-cylindrical sections are gradually increased in thickness as they extend from the flanges 18 so as to provide a relatively thick wall at the uppermost portions thereof, as indicated by the numeral 21. Arranged in the opposite sides of the semi-c lindrical sections are rows of openings 22 or permitting the air in the chambers to escape into the fire box. It will be noted that there are two rows of openings on each side of the semi-cylindrical sections and that each opening is gradually reduced in size as it extends outwardly so as to give a spraying effect when the air is forced therethrough under pressure. By providing the openings to the sides of the cylindrical members, the air from one chamber is directed towards the air from another chamber, thus giving a cross ire effect so as to thoroughly burn all combustible matter in the fire box and for eliminating the blasting of the fuel from the fire bok.A

grate In order that air may be supplied to the chambers formed by the semi-cylindrical'sections, I have provided a compressed air tank 23 which has communicationv through a main supply pipe 24 and branch supply lltl pipes 25 to the chambers. The branch pipes 25 extend through the forward portion of the floor and communicate wit-h the chambers at the lower forward ends of the semi-cylindrical members. In each of the branch pipes is provided a valve 26 for regulating the iow of air to the chambers which will control the burning of the fire in the fire box. Extending to the compressed air tank 23 is a pipe 27 having a cutoff valve 28 therein, said pipe leading from an air pump (not shown).

In operation, the fuel is placed in the lire boX through the doors 13 in the forward end of the furnace and upon the upper surfaces of the. semi-cylindrical members 17, which together with the fire bricks i9 support the fuel in the fire box. The air under pressure from the tank 23 is forced through the tapered openings 22 for causing a draft in order that the fuel may burn, the fire being regulated by the valves 26 which conf trol the flow of air. It can thus be seen that the small particles of coal placed in the fire box will not be permitted to drop through the grate as in furnaces now in use, and that the loss of coal due to falling through the grat-e and being blasted out of the furnace is eliminated, thus minimizing the consumption of fuel. As the semi-cylindrical sections are of much greater thickness at their uppermost portions, it can also be seen that when the walls of the sections are highly heated due to the fire thereon, the same will not sag. or become ydistorted due to the weight of coal pressing thereupon.

Having thus described my' invention, what VI claim as; new is: v

In a. grate structure a series of hollow bodies closed at their ends, said bodies being arched transversely and the bodies being provided at their edges with outstanding flanges which completely circuinscribe the STEPHEN S. S. KENNEDY. 

